There has been a major (POSITIVE) mind shift in the recreational fishery with regards to the practice of catch and release angling. This has mainly been driven by the increase in the use of social media to share our “catch of the day” and TV shows.
Catch and release is crucial for our ever depleting fish stocks however the aim of this is to ensure that the fish is returned to the water in a state which maximises its chances of survival. Many assume that a fish which swims away is fit to survive however a lot of research has looked into the stress a fish is exposed to during such an event and the immediate and prolonged effects on them. By understanding a few basic principles and applying appropriate measures we can increase the survival rate of the fish we release.
Probably the most important thing to take into account is the amount of time a fish is held out of the water. Just like we need to breathe, so does a fish and a good rule of thumb to live by is to hold your breath when you remove the fish from the water, when you need to breathe, so does the fish! We often don’t realise how long it takes to unhook the fish, measure, photograph etc. A study conducted, by Ferguson and Tufts 1992, revealed that fish, which were exposed to a similar stress as that caused by the fight, had a survival rate of 88% after being out of the water for 30 seconds. However, after 60 seconds survival rates dropped to 62% and after 60 of seconds exposure to air, survival was a mere 28%! There are a number of simple ways to reduce the amount of time we expose our fish to air. Hold fish in the water for as long as possible. In some cases fish can be held in nets while removing hooks. In many instances taking photos is the main reason why fish are held out of the water for prolonged periods of time. Have cameras ready (switched on and ready to snap away) before landing your fish so that photos can be taken straight away. In some cases buckets/nets can be used for fish to be placed in till you are ready to take the snap.
Removal of the hook is another factor which can influence fish survival post-release. The first thing to consider is hook type: using single hooks you increase the ease of removing the hook and consequently the tissue damage to the fish (trebles are nasty things – for both fish and angler!). Secondly, hook position – in many cases it is better for a deeply set hook to be left, it will eventually dissolve. Thirdly, a long nose pliers or hook remover can be used to reduce time taken to remove the hook.
How we handle the fish whilst removing hooks and taking photos is fundamental to successful catch and release practices.
- When handling a fish out of the water, it is best to ensure your hands are wet. This reduces the amount of slime which is removed from the skin of the fish. Fish slime (also known as the mucoprotein coating) acts as a protective coating, reducing the risk of attack from nasty pathogens.
- Support the fish. Hold the fish with one hand firmly under the belly and the other close to the tail. With bigger fish it is better to keep the fish in the water – there are many ways to take nice photos of large fish whilst they are still in the water. Alternatively make use of a boga grip – this is particularly useful for fish such as shad who have a tendency to shake their way out of your hands.
- DO NOT TOUCH THE GILLS! The gills of a fish are extremely sensitive and any damage to this organ will result in a slow death!
Once we have effectively landed our fish, removed the hook and taken our photo we are ready to release our catch. However, before we let our catch swim off it is often a good idea to revive the fish. Hold the fish gently by the tail and face it into the current, this allows for fresh water to pass over the gills and allow it to recharge itself with much needed oxygen. Once your fish is ready to forcefully kick out of your hands let it go and watch it grow!
Ferguson, R.A. and B.L. Tufts. 1992. Physiological effects of brief air exposure in exhaustively exercised rainbow trout (Oncorhynchus mykiss): implications for “catch and release” fisheries. Canadian Journal of Fisheries and Aquatic Sciences 49:1157-1162.